CHICAGO – The Astros’ ace-in-waiting got his turn and is still waiting.

You can tell that Bud Norris knows it’s there – the ability to fill the shoes of Wandy Rodriguez at the top of the rotation that he inherited from Roy Oswalt before him.

But even before Rodriguez was traded, it’s been a miserable season for Norris, who uses the word “frustrated” after just about every start and was so once again after the Astros’ 7-2 loss to the Cubs.

The story of Norris’ season, instead of an ascension to No. 1, has been alternately injuries and games that got out of hand on his watch, and Wednesday afternoon saw both.

Before he was lifted with a bruised left foot, the result of a kick-save on a comebacker, Norris allowed six runs on three home runs as the Cubs took advantage of a great day for hitting.

“I just felt like it was inconsistent and it felt like all the mistakes I made got punished,” Norris said. “It’s just frustrating because you’re trying to make good pitches and sometimes you do, sometimes you don’t. A couple of them got out of the park.”

Lefthanded hitter David DeJesus hit a couple on his own, doubling his season total in the span of two innings. He gave the Cubs a 2-0 lead with a solo shot to lead off the third, and after Alfonso Soriano whacked a two-run shot later in the inning, DeJesus piled on in the fourth with a blast to center.

The second DeJesus home run would be the penultimate batter for Norris and immediately followed a walk to pitcher Justin Germano. So while the comebacker ended his night, it was trending the wrong way already.

“Two of the home runs were preceded by a walk and you hate to see that,” manager Brad Mills said. “One of them was to the pitcher and you hate to see that.”

Norris will be re-evaluated Friday to determine if he needs to miss a start or push one back with the two off-days between scheduled starts allowing for a little flexibility. He took the shot from Josh Vitters pretty squarely and was wrapped after the game.

“I just had a ringing sensation in my foot, just tried to get it calm down and I knew with my landing foot it wasn’t going to be pretty,” Norris said. “I’m glad I just came out because I didn’t want to hurt it any worse than it was.”

If bad things happen in threes, Norris was already believing that. He had three injuries this year, a hip flexor issue in May, a knee sprain in June and now this.

He also counts three bad starts that have derailed his season to the point of a 5.23 ERA – the third highest among 54 qualified National League pitchers. In starts at Colorado, Arizona and Wednesday in Chicago, Norris allowed 24 runs in 9 1/3 innings.

“I’ve got a lot of good ones and a lot of bad ones,” Norris said. “Being consistent is something you’re trying to get and figure out. I think I did a good job with that last year and unfortunately there’s been a couple of really bad starts this year and I have to keep plugging away.”

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Tipping point: A 1-0 game started getting out of hand when the Cubs started going deep of Bud Norris, who is now tied for the Astros team lead with 19 home runs allowed with three Wednesday.

On the mound: After Norris left, the bullpen did commendable work with only an unearned run allowed in 4 2/3 innings from Chuckie Fick, Xavier Cedeno, Mickey Storey and Wesley Wright.

At the plate: When Scott Moore and Jose Altuve have five of the seven hits and they’re separated by three spots in the order, it’s not going to be a very productive afternoon.

Under the radar: Outs were coming two at a time all day. The Cubs hit into three double plays, while the Astros hit into four. Marwin Gonzalez alone hit into three, while the fourth ended a bases-loaded chance with only one run.